Watch The Tube: Going Underground |

Watch documentary | London's lifeblood under the microscope. Filmed over a year, this new obs-doc series goes behind the scenes for a revelatory look at the London Tube network, meeting some of the 20,000 workers that keep it running smoothly, despite countless daily logistical, engineering and safety challenges. Since becoming the world's first underground railway in 1863, the London Underground has grown to 270 stations and 11 lines stretching deep into the suburbs. Today, however, it is showing signs of age and with almost five million passengers every day, it is full to bursting. From the managing director to the emergency response team and from train drivers to station staff, this series follows staff undertaking critical activities that keep the tube moving every day.